Jakarta. A foreign vessel illegally fishing in the Philip Strait between Indonesia and Singapore was seized with a ton of methamphetamine on board, the Ministry of Maritime Affairs said on Sunday (11/02).

The boat, Sunrise Glory, under the Singapore flag was seized near Batam, Riau Islands, by the Indonesian Navy on Feb. 7.

The vessel had fake documents. Its four crew members, all Taiwanese, have been arrested.

The operation was conducted by the Navy, the National Narcotics Agency (BNN) and the ministry's task force for combating illegal fishing, Navy deputy chief Rear Adm. Achmad Taufiqoerrachman said in a statement.

He said BNN has been suspecting the vessel since 2017, but to avoid detection its crew were switching off the automatic identification system and frequently changed the ship's name.

"The success of the operation was due to joint efforts by the three institutions and information sharing, which allowed us to spot the ship that carried shabu [methamphetamine]," Achmad said.

Investigation is ongoing to find the masterminds behind the narcotics network.